The image below shows the track of the falling ball, as obtained using the Tracker software.
The plot on the upper left is the horizontal position versus time. The graph should be a flat line because the ball does not move left-to-right but it's hard to mark the exact position so the graph shows some random variation.
The lower plot of the vertical position versus time is more interesting. Notice that this plot is a parabolic arc. There are about 16 frames from apex to impact and the 8th frame (half way down in time) is about a quarter of the distance from the apex to the ground. The frame rate in this clip is 30 fps so it takes just over a half second for the center of the ball to fall a height of about five feet (Corey Tom, who is dropping the ball, is 5 foot 9 inches tall).
Here are some examples from last semester:
No comments:
Post a Comment